Formation of deep junction, particularly, for high voltage applications, requires high temperature and long thermal drive in process. The high temperature and long thermal drive in process, however, may lead to wafer warpage. To alleviate the thermal stress created during the drive in process, removal of pad nitride film on the backside of the wafer before the drive in process is desired. However, current pad nitride removal process requires long processing times. This leads to low throughput and higher manufacturing cost.
Therefore, it is desirable to provide an efficient and simplified method for wafer processing and with reduced manufacturing cost.